How to take an animation off an object thats parent to another
If I understand correctly you are looking for a heath bar that follows the camera's location but not all the little rotations caused by animations. You may be looking for the child of constraint. 



With these settings as the camera rotates on the x and y axis (like during a run animation) the cube does nothing. However, transform and rotation on the z axis by the camera affect the cube allowing it to always still be in view.